Bolster plate



June 1 1926.

F. w. (CHRISWELL BOLSTER PLATE Filed August 6, 1925 BY MM ATTORNEYPatented dune l, 192%,

FREDERICK W. CHRISWELL, OF SEATTLE, WASHINGTON.

BOLS'IEB PLATE.

Application filed. August 6, 1925.

This invention relates to improvements in bolster plates for use onlogging cars and the object of this invention is to provide a one piecebolster plate that is strong and durable in construction and that willnot be broken by ordinary use.

Another object is to provide a castmetal bolster plate shaped to fulfillcertainreqmrements but designedso as to avoid producing internalstresses and crystal deformation in the metal as the casting cools.

These bolster plates are commonly used on logging cars for supportingcar bunks thereon, the bolster plates resting on the is usual crossbolster of the car.

Bolster plates of this nature as heretofore constructed have not beensatisfactory, due to the fact that they are liable to break near thelocation of the central hub under ordias nary conditionof use. Thisweakness is not due to lack of the necessary weight or amount ofmaterial at the location where the breaks occur but ratherto the factthat the casting is shaped so that the crystals in the material at thatparticular location are deformed, compressed and left under permanentstress as the casting cools, thus leaving them in a state in which theybreak easily.

The present invention overcomes this difficulty by providing a bolsterplate that eliminates this deforn'iation in the material. l1 accomplishthe objects by devices illustrated in the accompanying drawings wherein,

l igure 1 is a riew in side elevation of a bolster plate constructed inaccordance with this invention.

Fig. 2 is a view in longitudinal midsec tion of the same. I

Figs. 3 and l are bottom and top plan views respectively of the same.

Figs. 5, 6. and 7 are views in cross section on broken lines 55, 66, and77 respectively of Fig. 3.

Referring to the drawings, throughout which like reference numeralsdesignate like parts, Figs. 1 to 7 inclusive indicate a preferred formof bolster plate of one piece integral construction and of substantiallyrectangular form that is adapted to be used upon the bolster of alogging car to support a relatively heavy log bunk on which logs arecarried. The weight of the lo" bunk 513 wholly upon the ends of theplate shown All 1 thereby fgi fii flilfllllg "smaller hub 18.

Serial No. 48,453.

a strain where the web members meet the outer hub member as indicated bythe arrows in Fig. 1. ihe bolster plate has a flat top side 12, as shownin Fig. l, and a bottom. side shown in Fig. 5, that is provided withcored portions 13 leaving at each side longitudinal webs 1d and midwaybetween the two sides other longitudinal webs 15 that are thickened, asat 16, near the center of the bolster plate.

A larger hub 1'? extends downwardly from the center of the bolster plateand a smaller hub 18 extends upwardly from the bottom 19 of the largerhub 17. The upper end of the smaller hub 18 has a hole 20 of smallerdiameter than the interior of said The webs l l and 16 all terminate inand are integral with the larger hub 17. The top side of the bolsterplate is cored, as at 21 and 22, to leave relatively long recesses inthe longitudinal medial plane of the plate and the inner ends of saidcored recesses 21 and 22 are cored deeper, as at 28 and 24, said deeperportions extending down between the walls of the larger hub portion 17and the small hub portion 18.

It will be noted that the thickened webs 16 on the bottom with therecesses 21, 22, 28, and 2% on the top leaves in effect two ribs ofmetal that extend continuously across the bolster plate on oppositesides of the hub 18.

Arcuate recesses 25 and 26 are formed in the top side of the bolsterplate to the front and rear of the center and extend down between hubs17 and 18, said recesses 25 and 26 are both undercut at both ends asindicated at 27 to reduce the weight of the bolster plate as much aspossible andyet leave relatively wide and substantial webs 28 of metalconnecting the central hub 18 with the remainder of the bolster platebody at four points between the cored recesses 25, 24, 26, and 23, twoof the webs 28 being on each side of the smaller hub 18.

It will be noted that the webs 28 on the top side and the widenedportions 16 of webs 15 on the bottom-side are all integrally connectedwith hub 17 thus greatly strengthen ing the structure and tending toprevent the bolster plate from breaking within or around the hubportion. Flanges 30 are provided both on the front and rear side of theholster plate to a Wider bearing surface Square corners and deeprecesses are avoided as much as possible in the construction around thehub so that when the bolster plate is cooling in the process of castingit will not be subjected to excessive strains sutiicient to deform thecrystals of the metal due to compression of the molding sand in pockets.

The invention shown provides the relatively wide webs 28, two on eachside of the smaller hub both extending continuously across the bolsterplate so as to prevent normal contraction of metal as the bolster platecools in casting. These webs are also located as to afford the greatestresistance to transverse breakage. ltbnormal stresses are also reducedby providing relatively shallow pockets with rounded corners so that thewedging of the molding sand and consequent deformation oi the crystalsof the metal in cooling will be reduced to a minimum. This is especiallyapparent in the provision of recesses 21 Q3 and 222l, the recesses 21and 22 extending well outwardly and tapering to points as shown and thecorners being rounded instead of square where recesses 21 and 22intersect recesses 23 am 2% respectively.

The foregoing description and accompanying drawings clearly disclose apreferred embodiment of this invention but it will be understood thatthis disclosure is merely illustrative and that such changes in thedevice may be made as are within the scope and spirit of the followingclaims.

hat I claim is 1. A bolster plate of the class described, embodying abody portion, two integral concentric hubs in said bolster platearranged in relatively spaced relation one within the other and aplurality of integral web members on each side of the longitudinalcenter line of said bolster plate extending across the space betweensaid two hub members.

2. A bolster plate of the class described, embodying a relatively longrectangular body member, a large integral hub extending downwardly fromthe center of said body member, a small integral hub extending upwardlywithin and spaced tron said larger hub, and two loi'lgitudinal websextending across the space between s: itl hubs on each side of thelongitudinal center line of said bolster plate and uniting with portionsof said smaller hub to form a ous metal bridge across the centralportion of said bolster plate.

3. A bolster plate of the class des ribed, embodying a relatively longbody member, two integral concentric hubs ot ditl'erent size disposedcentrally of said bolster plate and arranged concentrically one withinthe other in spaced relation, web members on the bottom side of saidbolster plate mid way between the two sides and having relatively wideportions that merge with said outer hub, said bolster plate havinglongitudinal recesses on its front side opposite said wider rib portionsand having longitudinal ribs on opposite sides of said recessesextending across the space between said two hubs and merging with saidinner hub.

4:. A bolster plate of the clas described embodying a relatively longbody member, a larger integral hub extending downwardly from the centerof said body member. a smaller integral hub extending upwardlyconcentrically within said larger hub and leaving an annular spacebetween the walls of said two hubs, webs on the bottom of said bolsterplates at the sides thereof and merging with said larger hub, other webson the bottom of said bolster plate mid way between the two sidesthereof and having relatively wide portions that merge with said outerhub, said bolster plate having longitudinal recesses on its top sidethat extend down into said wider web portions and are deeper atthelocation of said annular space between said two hubs and longitudinalribs on opposite sides of said recesses extending across the spacebetween said two hubs and being substantially tangent to said inner hub.

In witness whereof, I hereunto subscribe my name this th day of July, A.D. 192.3.

FREDERICK W. Clllll r ll lilili.

continu-

